Sara Ramirez in “Song Beneath the Song,” a special musical episode of “Grey’s Anatomy.”

The doctors and nurses on the TV drama “Grey’s Anatomy” do a lot of unusual things at Seattle Grace Hospital–they have sex in back rooms, they fight off crazed gunmen, and, on occasion, they’re even haunted by ghosts. On tonight’s episode, the cast will try something that maybe seems relatively realistic: they’ll break into song.

Tonight’s special musical edition of the show, titled “Song Beneath the Song,” will feature music that has previously appeared on the soundtrack (such as The Fray’s “How To Save A Life” and Brandi Carlile’s “The Story”); the episode was written by the show’s creator, Shonda Rhimes. The tunes will be performed by the actors on the program.

The episode is described as “Callie-centric” and will focus on Dr. Callie Torres, an orthopedic surgeon played by Sara Ramírez. Torres, who is pregnant by a male doctor but newly engaged to her girlfriend, was recently in car accident. [We can't tell you much more because we don't want to ruin the episode for fans; and don't worry, there are no spoilers in the interview.]

Born in Mexico, the 35-year-old Ramírez won a Tony for best featured actress in a musical in 2005 for her part in “Monty Python’s Spamalot.” On Sunday, she released on iTunes a mini-album of four songs, including three tracks she co-wrote and a new version of “The Story.” “Grey’s Anatomy” will air at 9 p.m. ET tonight on ABC.

Ramírez talked to the Wall Street Journal today about tonight’s episode, her music, and the future of her character.

Speakeasy: What did you think when they told you they were doing a musical episode of “Grey’s Anatomy”?

Sara Ramírez: Like most people I had fears that came up. Is it going to be horrible? Is it going to be cheesy? What are people going to think? Are they going to compare us to “Glee”? At the same time I felt very excited at the notion of being able to sing because I’ve been singing my whole life.

What made you decide you wanted to release a mini-album?

My grandfather was a singer, my mother was a singer. So it’s always been a part of my life, something that just came naturally to me ….We’ll see where it goes. I don’t have any expectations.

Do you plan to do any more movie or stage work in the near future?

Well, for now I’m really just working on “Grey’s Anatomy.” That takes 9-10 months out of your year right there. I’m open to whatever’s meant to be. Whether it’s film, stage, music—I’m open to all of it.

When I told wife I was talking to you about this musical episode, she was afraid they were doing the special show to kill off your character.

Our loyal fans have stuck by us through thin and thick. It’s exciting to be working with a show that takes risks. When I see fans getting upset about what may happen—not that we want people getting in a panic mode, but at the same time, it’s great that people are talking at all, whether it’s negative or positive. That they care enough to have a conversation about it. It’s fantastic.

When I heard you were still working on the set, I thought, okay, she can’t be dead. But then I thought—maybe she’s a ghost. They’ve done that before.

Well there’s post-production. The episodes are still having work done up until they air.

How difficult is it to play a character whose sexuality seems to be in flux?

What I love about Callie is she’s a very open person. She doesn’t judge herself about it. I think it’s very courageous for someone to step outside of the box they’ve grown up in that they have been in their whole life…She was with men her whole life and then met Dr. Hahn who kind of opened up her world to a new understanding of herself. She realized she’s attracted to the essence of a person instead of being focused on the gender. It’s not a journey I’ve seen portrayed often. She’s in a lesbian relationship, but she hasn’t been a lesbian her whole life. She’s not into labels.

Was there anyone on the cast who was terrified at the idea of a musical show because their voices weren’t strong enough?

Singing can be a difficult experience if you’ve never done it before. For some people it was a wonderful experience, and some had to work through some issues. It’s all great, it’s all good….The cast members who sing in the episode went in and sang for Shonda so she would get a sense of people’s voices and where it would fit best in the storytelling and in the songs. It went really great at the read-through where we read through the script for the first time and heard each other singing on the speakers that played the songs we had gone in to record. We hadn’t heard each other sing before. It was a wonderful moment. It really unified everyone and got us on the same page.

About Speakeasy

Speakeasy is a blog covering media, entertainment, celebrity and the arts. The publication is produced by Barbara Chai and Jonathan Welsh with contributions from the Wall Street Journal staff and others. Write to us at speakeasy@wsj.com or follow us on Twitter at @WSJSpeakeasy or individually @barbarachai.